As vibrational energy absorbing apparatuses (dampers) of this type, viscous dampers, friction dampers, lead dampers, steel bar dampers, and the like are known. Such a vibrational energy absorbing apparatus is applied to a structure together with such as a spring device for returning the structure to an initial position.
Patent Document 1: JP-A-2003-287079
Non-patent Document 1: Nakata, Temura, and Igarashi: “Pseudo-Negative Stiffness Added Type Semi-Active Vibration Control Experiment of Full-Scale Connected Structures,” Proceedings of the 56th JSCE Annual Meeting, Japan Society of Civil Engineers, October 2001, pp. 162-163.
Non-patent Document 2: Ienaga, Igarashi, and Suzuki: “Real-time Hybrid Test on Application of MR Dampers to Semi-Active Pseudo-Negative Stiffness Control”, Proceedings of the 2003 Annual Meeting of the Japan Association for Earthquake Engineering, pp. 268-269.